Engine fuel pump



' l.. PENGILLY 2,351,064

ENGINE FUEL PUMP K 7 OL Nilwl lo m@ W WN E :-1 5 `P Il ||.|L|| I Il Il ||||IH S I I.. Il M w Ev m 5 n L l 4 e. w t. p M 6/ 8 n //V//A/ `lune 13, 1944.

m lvl I Patented June 13, 1944 y UNITED STATES PTE OFFICE t ENGINE FUEL PUMAD Lewis engilly, Loma Mar, Calif.

Application September 8, 1941, Serial No. 409,942

s claims. (0.1.10'3-164) This invention relates particularly to a. fuel pump for an internal combustion engine wherein the fuel is raised from a fuel tank, placed at a lower level, to the level of the engine carburetor.

An object of the invention is to provide a pump of simple construction, together with piping and check valves, for supplying fuel to an engine carburetor which will automatically cease supplying fuel when the carburetor is full, and automatically replenish the supply when the level of gasoline in the carburetor falls.

A further object of the invention is to provide an apparatus for raising a liquid from one level to another which includes a pump for setting a column of liquid in pulsating motion by unidirectional impulses in combination with valves'operating in timed relation, to prevent return to the source of supply of the entire amount of liquid advanced and yet to accomplish the discharge of a part of the liquid advanced.

lThese and other objects will appear as the description of the invention advances.

In the drawing:

Fig. 1 is a schematic lay-out of an automobile engine and fuel tank having a pumping mechanism and piping, constructed in accordance with Y my invention (diagrammatically illustrated) applied thereto.

Fig. 2 is a vertical section through the fuel pump to the interior Construction thereof.-

Fig. 3 is a vertical section through the fuel tank, valve chamber assembly.

In detail the construction illustrated in the drawing consists of an internal combustion engine generally designated hy the numeral I, and a fuel tank indicated by 2. The engine I has a carburetor 3 thereon provided with the usual fuel bowl and float valve within the bowl.

The carburetor 3 is connected by a fuel pipe l to a valve chamber assembly 5 located within the fuel tank 2 near the bottom thereof to be submerged by the fuel.

On the engine I I have located a pump. Thel ports I2 and I3, the upper port I2 being an air inlet and the lower port I3 being a pressure outlet tothe valve chamber assembly in the fuelr tank. A passage lli is provided in the cylinder wall to connect the ports I2 and I3, which ports are located in a selected position in relation to the groove I in the piston to effect the working of the assembly as will be more fully disclosed hereinafter. The inlet or suction port I2 is provided with a check valve l5 to allow sufficient air to enter the cylinder in order that a maximum air pressure may be maintained when the pump is in operation.

The'valve chamber 5 is provided with separated check valves I6 and Il therein, the valve I6 being in the bottom of the chamber 5 and the valve Il being in the fuel line and above the valve I6.

The assembly operates to pump fuel from the tank 2 to the carburetor 3 as follows:

Upon operation of the engine I, the pump 6 is put in motion. O-n the down stroke of the piston 9, a suction is created in the cylinder head,

which reacts through the air line I to lift the bottom check valve I5 and suck fuel through the screen strainer I8 into the chamber 5; but the A `force of this suction is limited by the springseated check valve I5 which will open occasion-` ally to replenish air inl the line l to the 'extent`4 that such air is mixed with the fuel in chamber 5 and passed along to the carburetor therewith'.

On the up stroke of the piston a pressure is created which causes the air inlet valve I5 to close and accumulated air pressure above the piston 9 to pass downwardly through the hole I I, to the piston groove I0 through which it passes to `the outlet port I3 and thence through the air line I to the valve chamber 5. The pressure in the valve chamber 5 forces the fuel contained therein upwardly and outwardly through the check valve Il, and fuel line Il to the fuel bowl of the Acarburetor 3.

On the following strokes of the piston the action above described is repeated.

The check valve I6 is calibrated so that when the'pump is not in operation, the valve chamber 5 and theV end of the fuel line I within the fuel of fuel within the valve chamber 5;"

The pump G is so constructed that the suction 'i stroke of the piston creates only a small amount of suction capable of drawing fuel through the inlet valve I6 into the chamber 5, and up into the air line 1 to a height slightly above the level i a constant pressure sufficient for the proper operation of the carburetor. However the pump will not create a pressure in the valve chamber 5, greater than is necessary to supply fuel to the carburetor properly regardless of the number of times the pump operates and regardless of how fast or how slow the fuel may be releasedy through the carburetor.

While I have shown the inlet port I3 located in the cylinder wall so as to register with the piston groove IB when the piston is at the top of the stroke, the same effect could be accomplished by providing the inlet through the cylinder wall to communicate with the piston groove I0 when the piston is at the bottom of its stroke.

Having thus described this invention, what I claim and desire to sec-ure by vLetters Patent is:v

1. In a liquid elevating system which includes av chamber having an outwardly seating inlet valve and an inwardly seating outlet valve, a delivery pipe controlled by thelatter valve and an air pipe leading to said chamber, a pump comprising a cylinder, a piston reciprocable therein, saidcylinder having a port opening into said air pipe, means for releasing a pressure impulse through said'port substantially at the end of the compression stroke of the piston and applying a suction impulse to said air pipe upon the return stroke, Vand means automatically limiting the degree of vacuum created in the air pipe bysaid suction impulse. f

2. yfIn a liquid elevating system which includes ar chamber'having 'an outwardly seating inlet valve and an inwardly seating outlet valve, av delivery pipe controlled by the latter valve and an airpipefleading to said chamber, a pump comprising a cylinder, Va piston reciprocable therein creating alternate pressure and suctionV impulses, said cylinder having a port opening into said airpipe, means for releasing the pressure impulses to saidchamber'through said port and meansv limiting the corresponding suction' impulses 'acting through said port to produce a series of impulses eiective principally in one' direction for elevating liquid from said chamber.

3. In a liquid elevating system which includes a chamber having an outwardly seating inlet valve and an inwardly seating outlet valve, a delivery pipe controlled by the latter valve and an air pipe leading to said' chamlbcna 'pump comprising a cylinder, anda piston reciprocable therein, said pump having a pressure outlet port` opened by the piston substantially at the end ol` its compression stroke and a suction portopened by -thev piston during its return stroke, said suc-` tion-port communicating simultaneously `with the air pipeleading to-said chamber and with an air l inlet admitting ratmospheric Ypressure and thus limiting the suc-tion and replenishing air-expelled from the air pipe by the compressi/on stroke. i

vdisposed/at .alevel normally below the point at pulses from the pump through said port to said chamber, and means limiting the correspondingv suction impulses to produce a series of im- -pulses effective principally in one direction for elevating liquid from said chamber, said pump being mounted above the level of liquid in the chamber and a portion of said air pipe extending above the chamber to a level higher than that to which thelimited suction is capable of elevating the liquid.A

6. In a liquid elevating system, a continuously operablefpump including a cylinder with a piston4 reciprocable therein, a liquid fuel supply tank disposed at a level normally below the point at which the liquid is delivered and below the level of the" pump, -a chamber submerged in said tank having an outwardlyv seating inlet valve and an inwardly seating outlet valve, a delivery pipe controlled by the outlet valve and leading to the point of delivery, an air pipe connecting said chamber with the pump cylinder, the connection-being Vby way of a port in the cylinder, meansfforr releasing a pressure impulse through said Yport substantially at the end of the compression strokeof the-piston, and means automatically admitting atmospheric air to the cylinder during eachreturn stroke of the piston except when the flow of liquid is resisted at the point of delivery, causingfthe cylinder pressure to remain above a predetermined limit throughout the pump cycle.

7: In aliquid elevating system, a continuously operable pump including a cylinder with a piston reciprocable therein, aliquid fuel supply tank which the liquid is delivered and below the level of' the pump, a chamber submerged in said tank having an outwardly seating inlet valve and an inwardly'seating outlet valve, a delivery pipe controlled by the outlet valve and leading upwardly and directly to the point of delivery, an air pipe-connecting said chamber with the pump .cylinder,the connection being by way of a port inthe cylinder, means for releasing a pressure impulse through said port to said chamber substantially at the end of the compression stroke of the piston, and means limiting the corresponding .suction impulse appliedY to said air pipe upon the returnV stroke whereby the pressure impulses operate to advance liquid from the chamber toward the point of. delivery and the limited suction impulses insure opening of the inlet valve Vof-.s'aid chamber.

adjustable-to vary the spring tension by which the check valve is ,heldseated 1 LEWIS PENGILLY 

